Abstract Details

Name: Asoke Sen
Affiliation: Assam University
Conference ID: ASI2020_489
Title : The interstellar comets and evolution of our solar system
Authors and Co-Authors : Asoke Kumar Sen
Abstract Type : Invited
Abstract Category : Sun and the Solar System
Abstract : It is generally agreed upon that, Sun along with all its planets, asteroids , comets and other sub-planets were formed some 4.6 billion years ago out of a single massive body called primordial solar nebula. All the current theories about the evolution of our solar system suggest that, the comets were formed near the Jupiter and later due to perturbation by the giant planet, were transported out to a shell like structure called Oort cloud ( at 10^5 to 10^6 AU from Sun). This process had an efficiency of 10% and rest 90% were lost into the interstellar medium. As we understand the Sun should be a typical star and there are many planetary systems like ours in our galaxy, so the stars in our galaxy together should have contributed a large number of comets into the interstellar medium. Such comets would not be gravitationally bound to any individual star and may occasionally get intercepted by our Solar system. From earth as we observe, can distinguish these comets from own solar system ones, by their hyperbolic orbits. The recent detections of two such interstellar comets Oumuamua and Borisov have now confirmed the theoretical predictions made by Sen and Rana in this regard, way back in 1993. These interstellar comets should carry the materials from other exosolar systems, into our own solar system. We can even conduct in-situ and sample return missions to study such comets. Apart from the remote ground based observations, since 1985 comets are being studied by close fly-byes and in situ observations. Very recently many sample return missions were carried out to comets. After such space missions we have understood many details about the evolution of our solar system, but at the same time a new set of questions about the formation mechanism of our solar system has come up. These details will be discussed.